More secrets about pets will apparently be revealed, as Illumination Entertainment continues to be successful and a movie based on an original idea is shown to be a winner this summer.

A sequel to the Illumination Entertainment film “The Secret Life of Pets” will be released in 2018. “Secret” opened in July and became a big hit, with the film currently ranking as the seventh-highest-grossing film of the year.

“Secret” is the newest hit for Illumination Entertainment (which was acquired by Universal Studios), which is also behind the “Despicable Me” film series (of which the 2015 animated hit “Minions” is also a part) and such recent Dr. Seuss films as “The Lorax."

At the time of its release, Associated Press writer Sandy Cohen wrote in a movie review that "Pets" has a “playful premise, endearing performances, and outstanding score ... It's fun to imagine what pets get into when no one is home, and ‘Pets’ does a great job of taking that idea to an extreme.”

Recently, Illumination Entertainment has made the middle of summer its business. It released “Despicable Me,” “Despicable Me 2,” and “Minions” in early July and all became big hits. “Pets” followed this pattern.

Anthony D’Alessandro of Deadline wrote at the time of the initial box office success of “Pets,” “You can’t deny the post-July 4th date worked in ‘Pets’’ behalf. In the wake of ‘Despicable Me 1’ & ‘2’ and ‘Minions,’ audiences have come to expect a hysterical, satirical toon at this time of year.”

Meanwhile, “Pets” becoming such a big hit is positive because it’s based on a new story and concept, writes Meriah Doty of TheWrap.

“‘Secret Life of Pets’ spells good news for original ideas in Hollywood,” Ms. Doty wrote.